That means right-hander Juan Nicasio, who has been inconsistent, and veteran Roy Oswalt, who is getting a look at the end of this season and will likely be invited back next, will be among competitors for the other two spots.

"As I see it right now, those three guys have really solidified a spot," Weiss said. "Juan's been good at times, but we need to see a little more consistency. But the other three guys, they're nice arms to have."

So the Rockies, who need a strong finish to avoid finishing last in the National League West in consecutive years for the first time in club history, enter 2014 in better shape than this year. De La Rosa, Chacin and Nicasio were coming off injuries in 2013.

But, it sets up dramatic competition at the back of the rotation.

Nicasio has won jobs in camp the last three years. Oswalt figures to be a low-risk competitor. Left-hander Drew Pomeranz, possibly righty Chad Bettis if he isn't made a reliever, and righty Collin McHugh also could be in the mix. Also figuring to be in the mix is 2012 supplemental first-round Draft pick Eddie Butler, a right-hander who went a combined 9-5 with a 1.80 ERA at Class A Asheville and Modesto and Double-A Tulsa. It is expected that he will be invited to Major League camp.

The X-factor is competition acquired in trades or on the free-agent market. The Rockies aimed low last year, bringing in lefty Jeff Francis and picking up righty Jon Garland after he was released by the Mariners in Spring Training. Weiss refused to speculate on free agency efforts, since those are upper-management decisions.

"You take a look at a pool of players who are available," Weiss said. "That's stuff for the offseason, and it changes quickly."